Measuring adherence to antiretroviral therapy in northern Tanzania: feasibility and acceptability of the Medication Event Monitoring System

Abstract

BackgroundAn often-used tool to measure adherence to antiretroviral therapy (ART) is the Medication Event Monitoring System (MEMS), an electronic pill-cap that registers date and time of pill-bottle openings. Despite its strengths, MEMS-data can be compromised by inaccurate use and acceptability problems due to its design. These barriers remain, however, to be investigated in resource-limited settings. We evaluated the feasibility and acceptability of using MEMS-caps to monitor adherence among HIV-infected patients attending a rural clinic in Tanzania's Kilimanjaro Region.MethodsEligible patients were approached and asked to use the MEMS-caps for three consecutive months. Thereafter, qualitative, in-depth interviews about the use of MEMS were conducted with the patients. MEMS-data were used to corroborate the interview results.ResultsTwenty-three of the 24 patients approached agreed to participate. Apart from MEMS-use on travel occasions, patients reported no barriers regarding MEMS-use. Unexpectedly, the MEMS-bottle design reduced the patients' fear for HIV-status disclosure. Patients indicated that having their behavior monitored motivated them to adhere better. MEMS-data showed that most patients had high levels of adherence and there were no bottle-openings that could not be accounted for by medication intake. Non-adherence in the days prior to clinic visits was common and due to the clinic dispensing too few pills.ConclusionMEMS-bottle use was readily accepted by patients. Although the MEMS-bottle was used accurately by most patients, patients need to be more explicitly instructed to continue MEMS-use when travelling. Even HIV-clinics with sufficient staff and free medication may impose structural adherence barriers by supplying an insufficient amount of pills.

Binge drinking is associated with differences in weekday and weekend adherence in HIV-infected individuals

“…Although microelectronic monitors may overestimate (individuals may open the bottle and not take the medication) or underestimate (individuals may remove more than one dose when they open the bottle) adherence (Bova et al, 2005), they have been shown to be more accurate than self-reported measures in both high and low income countries (Arnsten et al, 2001; Deschamps et al, 2004; Hugen et al, 2002; Lyimo et al, 2011; Vriesendorp et al, 2007). There are limitations to our study.…”

Ethical Questions in Medical Electronic Adherence Monitoring

“…First, if the individual's choice to continue using the EAM is voluntary, it is usually safe to assume that she genuinely wants to be more adherent, and thus, when she succeeds in doing so, that EAMs help her fulfill her own autonomous will. 10 This response is irrelevant in situations in which individuals choose to forgo therapy, such as therapy perceived to be futile or too toxic. One could also argue that what the EAM user Bloses^while using the EAM-primarily the freedom to remain sick or untreated-is of little objective value to the individual.…”

“…21 The extent to which someone tolerates loss of privacy or confidentiality is culturally and individually relative. 22 For instance, while HIV patients in India and Malawi 23 and in the United States 24 have expressed concerns that electronic pill bottles could raise suspicion from family and neighbors, such concerns were not raised by HIV patients in Uganda, 5 Tanzania, 10 or South Africa. 25 The heterogeneous findings of these studies may reflect variations in individual or cultural conceptualization of privacy and confidentiality, in criteria for what counts as a breach, or differences in disease-associated stigma.…”

Low levels of HIV-1 drug resistance mutations in patients who achieved viral re-suppression without regimen switch: a retrospective study

“…The emergence of HIV drug resistance mutations (DRMs) is influenced by many factors, foremost of which is adherence to antiretroviral therapy (ART) [2,3]. Adherence to ART can be measured by various methods [4], including MEM system [5], face-to-face interviews [2,3], self-reported adherence [6], review of pharmacy refill pick-ups, [7] and measuring blood or hair antiretroviral (ARV) levels [8]. It has long been accepted in clinical practice that an intermediate level of adherence at 70-89% is associated with higher risks of VF and detection of DRMs as compared with patients having high (≥90%) or low (< 70%) levels of cumulative adherence [2].…”